下列选项中，说法正确的一项是 ( )。

A．该省失业人口人数随着年龄的增长持续下降

B．城镇各年龄段失业人数均低于全省相应年龄段失业人数

C．该省失业人员特点之一为失业人口年龄构成较轻

D．该省非城镇人员失业情况比城镇人员更严重

It was ______ he does ______ makes his students enthusiastic about school.[ ]

A. that; that

B. what; what

C. that; what

D. what; that